1. Field of the Invention
The present invention relates to an apparatus for detecting electromagnetic waves and protecting eyes from glare, and more particularly to an apparatus for detecting electromagnetic waves and protecting eyes of a worker from glare which detects not only high-intensity light generated in welding or cutting environments but also an electromagnetic wave generated in the same to safely protect the eyes of the worker.
2. Description of the Related Art
Generally, workers use a welding light detection and anti-glare eye protection apparatus placed on their head to adjust the transmittance of light, generated by a welding or cutting torch, through an anti-glare eye protection plate of the apparatus. The apparatus typically uses an optical detector to detect light generated by the welding or cutting torch.
FIG. 1 is a perspective view of a protection mask having a conventional anti-glare eye protection apparatus.
As shown in FIG. 1, a protection mask 1 having an anti-glare eye protection apparatus 2 and solar cell 3 mounted at a front portion of the protection mask 1 reduces the intensity of light entering eyes of a worker through an anti-glare eye protection plate 5 which is a liquid crystal display (LCD) included in the anti-glare eye protection apparatus 2.
More specifically, a photosensor 4 such as a photodiode provided on the anti-glare eye protection apparatus 2 at a front portion thereof senses light generated by the welding or cutting torch. Based on the detected light, a control circuit included in the anti-glare eye protection apparatus 2 controls the anti-glare eye protection plate 5 to be darkened so that the intensity of light passing through the anti-glare eye protection plate 5 is reduced, thereby protecting eyes of the worker who wears the protection mask 1.
FIG. 2 illustrates a user interface for adjusting shade, optical detection sensitivity, and time delay of the conventional anti-glare eye protection apparatus 2.
As shown in FIG. 2, the user interface of the conventional anti-glare eye protection apparatus 2 includes a shade adjuster 6, an optical detection sensitivity adjuster 7, and a time delay adjuster 8.
The shade adjuster 6 is used to adjust a shade level of the anti-glare eye protection plate 5. The shade level indicates the level of darkness of the anti-glare eye protection plate 5. Light transmittance of the anti-glare eye protection plate 5 is controlled by adjusting the shade level using the shade adjuster 6.
The optical detection sensitivity adjuster 7 is used to adjust the sensitivity of optical detection. The optical detection sensitivity has a numerical value indicating the degree of response of the control circuit in the anti-glare eye protection apparatus to an output signal of the photosensor 4. As the optical detection sensitivity increases, the responsiveness to low illumination increases.
The time delay adjuster 8 is used to adjust time delay of the anti-glare eye protection apparatus 2. If the time delay has a low value, the control circuit of the anti-glare eye protection apparatus 2 quickly switches the anti-glare eye protection plate 5 from a dark state to a bright state upon detecting through the photosensor 4 that welding has been finished. On the other hand, if the time delay has a high value, it takes a long time to switch the anti-glare eye protection plate 5 from a dark state to a bright state.
The industry of anti-glare eye protection apparatuses generally uses a shade level in the range of 5-13, optical detection sensitivity in the range of 0-10, and time delay in the range of 0-10.
The user interface of the conventional anti-glare eye protection apparatus 2 further includes a power switch 9, a power switch used to power on or off the apparatus, a battery 10 to supply power, and a low voltage indicator 11 indicating a low voltage level of the apparatus.
However, when using only the optical detector to detect welding light, the apparatus often operates abnormally due to interference light and variations in the level of detected signals depending on the type of welding or the type of welder.
When low-current welding, outdoor welding, or thin metal welding is performed, the optical detection sensitivity is typically set to be high. If the optical detector is used alone in this case, the apparatus may operate abnormally since it responds to interference light. For example, although the anti-glare eye protection plate 5 must be brightened, it may remain in a dark state or otherwise may be slowly switched to a bright state.
A known anti-glare eye protection apparatus further includes an electromagnetic wave detector for preventing such malfunctioning.
The anti-glare eye protection apparatus including such an electromagnetic wave detector can efficiently control the transmittance of light of the anti-glare eye protection plate through electromagnetic wave detection in environments, in which it is difficult to identify welding light since ambient illumination is high and thus light other than welding light is also detected, as when outdoor welding is performed with direct exposure to sunlight, when low-current welding is performed with low-intensity welding light, or when a lighting that provides high and direct illumination to a welding target is used.
The conventional electromagnetic wave detection and anti-glare eye protection apparatus includes a rod-shaped coil (electromagnetic wave sensor) to sense high voltage-induced electromagnetic waves generated when welding is performed. However, the rod-shape coil has a narrow sensing range. That is, the rod-shape coil has low sensitivity since it has narrow vertical and horizontal sensing ranges. This results in inaccurate electromagnetic wave detection.
In addition, the rod-shaped coil has poor sensitivity in a specific direction, which causes the apparatus to operate abnormally.